Sewing machine



Nov. 19, 1929. J. R. MOFFATT ET AL SEWING MACHINE Original Filed June 4, 1926- 2 Sheets-Sheet l Nov. 19, 1929.

J. R. MOFFATT ET AL 1,736,458

- SEWING MACHINE Original Filed June 4, 1926 2 Sheets-Sheet 2 m 619 ii! "x0133? '1 57 n 6 0 5;; l w) J I m) 65 'F o I I 02 J3 y j JJ glwuentqzs MM"W Patented Nov. 19, 1929 UNITED STATES PATENT OFFHCE JAMES R. MOFFATT, OF CHICAGO, AND RALPH S. KELSO, OF ROCKFORD, ILLINOIS, AS- SIGNORS TO UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A COR- PORATION OF ILLINOIS SEWING MACHINE Original application filed June 4, 1926,

Serial No. 113,714. Divided. and. this application filed December 23, 1927. Serial No. 242,118.

The invention relates to new and useful improvements in sewing machines, and more particularly to the construction and arrange ment of the operating mechanism for the parts which aremounted on and supported at the outer end of an overhanging arm.

An object of the invention is to provide a machine of the above type wherein the greater portion of the actuating mechanism for operating the needle bar, the thread finger and trimming mechanism, are all located in a hollow head at the free end of an overhanging arm.

A further object of the invention is to provide a machine of the above type wherein the needle bar is mounted in a relatively long bearing at its upper end, and said needle bar is shortened so that the upper end thereof during the reciprocations of the needle bar does not pass above the overhanging arm.

A further object of the invention is to provide a machine of the above type, wherein all of the actuated parts at the free end of the overhanging arm are operated by oscillating rock shafts located within and extending lengthwise of the overhanging arm.

These and other objects will in part be obvious and will in part be hereinafter more fully disclosed.

In the drawings which show by way of illustration one embodiment of the invention- Figure 1 is a view partly in section and partly in front elevation, showing a machine embodying the improvements;

Fig. 2 is a view of the front end of the machine with the cover plate removed from the overhanging arm to expose the parts within the same;

Fig. 3 is a sectional view on the line 3-3 of Fig. 2;

Fig. i is a perspectlve view of the oscillating member at the end of one of the rock shafts which imparts movement to the thread finger and to the trimmer, and

Fig. 5 is a view showing more or less diagrammatically a front view of the presser foot and the immediately associated parts.

In our co-pending application Serial No. 113,714, filed June 4;, 1926, there is shown and described a machine which includes a supporting standard carrying an overhanging arm, underneath which is located a cylindrical work supporting arm, off from the end of which the material is fed as it is stitched. The present application is a division of said prior application, and the invention herein is directed to the actuating devices and the arrangement thereof for operating the parts located at the free end of the overhanging arm. At the free end of the overhanging arm there is a needle bar carrying needles. This needle bar is mounted in bearings, and the upper bearing is elongated and the needle bar is shortened, so that during the reciprocation thereof, the needle bar does not raise above the upper end of the overhanging arm. The upper end of the needle bar is completely housed within the hollow needle head at the .outer end of the arm. The needle bar is reciprocated by means of a rock shaft which extends longitudinally of the overhanging arm and is mounted in three bearings disposed so as to form a very efficientrigid support for the rock shaft, thus reducing to a minimum any vibrations imparted from the rapid oscillation of the shaft to the parts in which it is mounted. Located in the hollow head at the end of the rock shaft is an arm which is connected by means of a link to the needle bar. Also mounted in this hollow head is a presser bar carrying a presser foot. Cooperating with the needles is a suitable looper and a cross thread laying device for forming covering stitches. Trimming devices are provided for trimming the fabric sections prior to the joining of the same by stitches. The trimming device includes a fixed blade and a movable blade. The fixed blade is mounted in the presser foot. The blades are horizontally disposed. The movable blade is operated by a rock shaft which is located in the overhanging arm and extends longitudinally thereof. This rock shaft terminates in a hollow head, and the actuating members for imparting oscillations to the trimming blade, are to a large extent, housed in the hollow head. The same is true of the actuating parts for the thread finger. Thus it is that the actuating parts are housed and protected from dust.

Referring more in detail to the drawings, the machine includes a suitable base 1 from which rises a standard 2. At the upper end of the standard there is an overhanging arm 3. This overhanging arm 3 is in the form of a hollow housing, as clearly shown in Fig. 1 of the drawings. The overhanging arm is provided at its outer endwith a hollow head, in which is located a needle bar 53. Mounted on this needle bar 53 are three needles 34, and cooperating with the three needles within the work supporting arm is a single looper 35 which is oscillated and moved laterally in the usual manner, so as to concatenate all of the needle thread loops.

The hollow head is provided with a relatively long bearing 5% which receives the upper end of the needle bar 53. There is a bearing 55 at the lower portion of the hollow head for the needle bar. The needle bar in its reciprocations does not pass above the upper bearing 54, so that the needle bar at the upper portion thereof is continually housed within the hollow head. Extendin length wise of the overhanging arm 3 is a rock shaft 56. This rock shaft is mounted in the bearings 57, 58 and 59, all of which are formed as a part of the overhanging arm. This rock shaft 56 is provided with an arm 60 which carries a ball stud at its outer end. A pitman 62 is connected to this ball stud, and this pitman cooperateswith an eccentric on the main shaft. Thus it is that the rock shaft 56 is oscillated. On the other end of the rock shaft is an arm 64. This arm 64 is connected by means of a link 65 to a lug formed as a part of a sleeve 66 which in turn is clamped to the needle bar. fits the rock shaft oscillates, it

- will oscillate the arm 6-1, and this will reciprocate the needle bar.

The material is held on the work support by a presser foot 67 carried by a presser bar 68. This presser bar is mounted in bearings 69 and 70, at the upper and lower ends, respectively, of the needle head. Mounted on the presser bar is a collar which is provided with a forked arm 71. This forked arm 71 straddles a guide bar 72 which is mounted in the bearing 70. The guide bar is stationary, and the forked arm 71 moves up and down thereon. The presser bar is raised by a rock shaft 73 which is mounted in suitable bearings in the overhanging arm and is provided with a collar '54 at its inner end. This collar in turn is provided with an arm 75 which projects through a slot in the casing forming the overhanging arm. A spring 78 encircles the rock shaft 73 and normally holds the arm raised. The presser bar 68 is moved downwardly until the presser foot engages the material by the usual form of leaf spring. On the end of the rock shaft 73 there is an arm 83 which underlies a lug on a sleeve 80. lVhen the operator depresses the arm 75 it oscillates the shaft 73, lifts the arm 83 into engagement with the lug which is attached to the presser bar, and thus it is that the presser foot is hit ed from the material.

The trimming mechanism which trims the fabric and prepares the edge of the fabric for stitching, includes a stationary trimming blade 84 mounted on the presser foot, and a movable trimming blade 85 carried by the arm 86 fixed to the lower end of a yoke 87. The yoke 87 is mounted on the presser bar 68 so that it oscillates freely about a vertical axis on the presser bar. The yoke is moved against the stationary blade, and at the same time, both blades may be raised and lowered with the presser foot.

Cooperating with the needles 34: is a thread hook or linger 90. This thread hook or finger 90 is carried by an arm 91 mounted on a yoke 92. The yoke 92 is freely mounted on the presser bar. One arm of the yoke 92 is directly above the bearing 70, and the other arm of the yoke is directly beneath the bearing 70. This forms a construction whereby the yoke may be readily oscillated on the presser bar, but the yoke is not raised and lowered within the presser bar. In other words, the presser bar slides freely with the yoke 92. Mounted in the overhanging arm is a rock shaft 93 which extends longitudinally thereof. This rock shaft 93 is provided with an arm 94 at its inner end, which arm carries a ball stud 95. A pitman cooperating with an eccentric on the main shaft engages this ball stud, and thus imparts oscillation to the rock shaft 93. The rock shaft 93 has a rigid head 98 at its outer end. This head 98 carries an arm 99 (see F 4) which projects through a. slot in a cover plate 100. At the outer end of the arm 99 there is a link 101. This link is connected at its other end to a ball stud 102, carried by an arm 103 formed integral with the yoke 87. The head 98 is also provided with a depending arm 104, and this depending arm 10 i is connected by a link 105 to a ball stud 106cmried by the yoke 92, which supports and .operates the thread finger 84:. The depending arm 10% passes through a slot in the lower part of the overhanging arm.

It will be noted that all of the mechanism between the rock shaft 56 and the needle bar is housed within the head at the end of the overhanging arm. It will also be noted that a large portion of the actuating mechanism for the hook, and for moving the trimming blade, is likewise housed w'thin the hollow head. Thus it is that the moving parts are protected from dust and lint. Furthermore, by this arrangement of parts, the region where the stitches are formed, and the trimming takes place, is comparatively free from obstructions and open to view by the operator of the machine.

It is hardly thought necessary to describe the threads or the tensions therefor, or the take-ups, as the present invention is directed particularly to the actuating parts for the needle, the tri nner and the thread hook, all of which are housed in this hollow head at the outer end of the overhanging arm, except the actuating rock shafts themselves, which are housed within the hollow arm and extend lengthwise thereof.

It is obvious that minor changes in the details of construction and arrangement of the parts may be made without departing from the spirit of the invention as set forth in the appended claims.

Having thus described the invention, what we claim as new and desire to secure by Letters-Patent, is

l. A sewing machine including in combination, an overhanging arm, a hollow head at the outer end thereof, a needle bar mounted for reciprocation in said hollow head, a rock shaft located within and extending lengthwise of said overhanging arm and connected to said needle bar for reciprocating the same, a trimming mechanism supported by said overhanging arm and including a movable trimming blade, a second rock shaft located within and extending longitudinally of the overhanging arm and terminating in said hollow head, and means located within said hollow head and actuated by said second rock shaft for oscillating said movable trimming blade.

2. A sewing machine including in combination, an overhanging arm, a hollow head at the outer end thereof, a needle bar mounted for reci arocation in said hollow head, a rock shaft located within and extending lengthwise of said overhanging arm and connected to said needle bar for reciprocating the same, a trimming mechanism supported by said overhanging arm and including a movable trimming blade, a second rock shaft located within and extending longitudinally of the overhanging arm and terminating in said hollow head, means located within said hollow head 'and actuated by said second rock shaft for oscillating said movable trimming blade, presser foot, a presser bar mounted in said hollow head and carrying said presser foot, a third roc; shaft located within and extending longitudinally of said overhanging arm, said last-named rock shaft terminating in said hollow head. and means operated thereby for raising said presser bar.

A sewing machine including in combination, an overhanging arm, a hollow head at the outer end thereof, a needle bar mounted for reciprocation in said hollow head, a rock shaft located Within and extending lengthwise of said overhanging arm and connected to said needle bar for reciprocating the same, a trimming mechanism supported by said overhanging arm and including a movable trimming blade, a second rock shaft located Within and extending longitudinally of the overhanging arm and terminating in said hollow head, means located within said hollow head and actuated by said second rock shaft for oscillating said movable trimming blade, a cross thread laying mechanism supported by said overhanging arm and includ ing a movable thread hook, and means located in said hollow head and actuated by said second-named rock shaft for oscillating said hook.

l. A sewing machine including in combination, an overhanging arm, a rock shaft mounted in said overhanging arm, a needle bar mounted in said overhanging arm, a link located in said overhanging arm and connecting said rock shaft to said needle bar, a presser bar mounted at the outer end of said overhanging arm, a presser foot carried thereby, a stationary trimming blade mounted on the presser foot, an oscillating yoke mounted on the presser bar, a movable trimming blade carried by said yoke, said yoke at the upper end thereof being located in the overhanging arm, a rock shaft in said overhanging arm, and means operated by said rock shaft for oscillating said yoke.

5. A sewing machine including in combination, an overhanging arm, a rock shaft mounted in said overhanging arm, a needle bar mounted in said overhanging arm, a link located in said overhanging arm and connecting said rock shaft to said needle bar, a

presser bar mounted at the outer end of said overhanging arm, a presser foot carried thereby, a stationary trimming blade mounted on the pi'esser foot, an oscillating yoke mounted on the presser bar, a movable trimming blade carried by said yoke, said yoke at the upper end thereof being located in the overhanging arm, a rock shaft in said overhanging arm, means operated by said rock shaft for oscillating said yoke, a thread laying finger, a yoke mounted on the presser bar and carrying said finger, said roe shaft for actuating the movable trimming blade having a depending arm extending through a slot in the overhanging arm, and means for connecting said depending member to said thread finger.

6. A sewing machine including a hollow overhanging arm, a rock shaft mounted in said arm, and terminating short of the forward end of the arm, a needle bar reciprocating in the forward end of said overhanging arm, a link connecting said needle bar to said rock shaft, a second rock shaft in said overhanging arm, a movable trimming blade mounted at the outer end of said overhanging arm, a thread finger mounted at the outer end of said overhanging arm, a head mounted on the end of said second rock shaft and having two arms arranged at an angle to each other, means for connecting one of said arms to said movable trimming blade, and means for connecting the other arm to said thread finger.

7. A sewing machine including a hollow overhanging arm, a rock shaft mounted in said arm and terminating short of the forward end of the arm, a needle bar reciprocating in the forward end of said overhanging arm, a link connecting said needle bar to said rock shaft, a second rock shaft in said overhanging arm, a movable trimming blade mounted at the outer end of said overhanging arm, a thread finger mounted at the outer end of said overhanging arm, a head mounted on the end of said second rock shaft and having two arms arranged at an angle to each other, means for connecting one of said arms to said movable trimming blade, means for connecting the other arm to said thread finger, a third rock shaft located in said overhanging arm, presser bar mounted in said overhanging arm, a presser foot carried thereby, and means operated by said third rock shaft when the same is oscillated for raising the presser bar and the movable trimming blade.

8. A sewing machine including in combination, a support, an overhanging arm extending across the upper end of said support, said overhanging arm having three bearings therein, a rock shaft mounted in said bearings, an arm in said rock shaft located between two of the bearings and directly above the support for the overhanging arm, a needle bar in the outer end of said overhanging arm, a link in said overhanging arm connected to said needle bar, a housing in front of and connected to said support, a main shaft in said housing, a crank in said main shaft, a pitman cooperating with said crank, a ball stud on said arm to which the other end of the pitman is connected, a second rock shaft located in two of the hearings in the overhanging arm and terminating above said support, an eccentric on said main shaft, an arm on said second rock shaft, a ball stud on said arm to which said eccentric strap is connected, a movable trimming blade, a thread finger, said second shaft terminating in the overhanging arm at the free end thereof, and devices connected to the outer end of said second rock shaft and to said trimming blade and thread finger for actuating the same.

In testimony whereof, we affix our signatures.

JAMES R. MOFFATT. RALPH S. KELSO. 

